package 三栈;

import java.util.Scanner;

/**
 * 用单项链表实现栈
 *
 * @Author XuZhuHong
 * @CreateTime 2021/9/10 23:20
 * @date 2021/09/10
 */
public class LinkedListStackDemo {
    public static void main(String[] args) {
        //测试一下 栈.ArrayStack 是否正确
        //先创建一个 栈.ArrayStack 对象->表示栈
        LinkedListStack stack = new LinkedListStack(4);
        String key = "";
        boolean loop = true; //控制是否退出菜单
        Scanner scanner = new Scanner(System.in);
        while (loop) {
            System.out.println("show: 表示显示栈");
            System.out.println("exit: 退出程序");

            System.out.println("push: 表示添加数据到栈(入栈)");
            System.out.println("pop: 表示从栈取出数据(出栈)");
            System.out.println("请输入你的选择");
            key = scanner.next();
            switch (key) {
                case "show":
                    stack.list();
                    break;
                case "push":
                    System.out.println("请输入一个数");
                    int value = scanner.nextInt();
                    stack.push(value);
                    break;
                case "pop":
                    try {
                        int res = stack.pop();
                        System.out.printf("出栈的数据是 %d\n", res);
                    } catch (Exception e) {
                        // TODO: handle exception
                        System.out.println(e.getMessage());
                    }
                    break;
                case "exit":
                    scanner.close();
                    loop = false;
                    break;
                default:
                    break;
            }
        }
        System.out.println("程序退出~~~");
    }
}

/**
 * 队列
 */
class LinkedListStack {

    private LinkedList head;
    private int maxSize;

    public LinkedListStack(int maxSize) {
        head = new LinkedList(0);
        this.maxSize = maxSize;
    }

    //入栈
    public void push(int value) {
        if (isFull()) {
            System.out.println("满了");
            return;
        }

        LinkedList linkedList = new LinkedList(value);
        linkedList.setNext(head.getNext());
        head.setNext(linkedList);

    }

    //出栈
    public int pop() {
        if (isEmpty()) {
            throw new RuntimeException("空了");
        }
        int value=head.getNext().getValue();
        head.setNext(head.getNext().getNext());
        return value;
    }

    //遍历
    public void list() {
        if (isEmpty()) {
            System.out.println("空了");
            return;
        }

        LinkedList temp = head.getNext();
        while (temp != null) {
            System.out.println(temp);
            temp = temp.getNext();
        }
    }

    //是否满
    public boolean isFull() {
        boolean flag = true;
        LinkedList temp = head.getNext();
        for (int i = 0; i < maxSize; i++) {
            if (temp == null) {
                flag = false;
                break;
            }
            temp = temp.getNext();
        }
        return flag;
    }

    //是否空
    public boolean isEmpty() {
        if (head.getNext() == null) {
            return true;
        }
        return false;
    }


}

/**
 * 节点
 */
class LinkedList {
    private int value;
    private LinkedList next;

    public LinkedList(int value) {
        this.value = value;
    }

    @Override
    public String toString() {
        return "栈.LinkedList{" +
                "value=" + value +
                '}';
    }

    public int getValue() {
        return value;
    }

    public void setValue(int value) {
        this.value = value;
    }

    public LinkedList getNext() {
        return next;
    }

    public void setNext(LinkedList next) {
        this.next = next;
    }
}
